SMAP @ JPL

SMAP (Soil Moisture Active Passive) is JPL's current satellite mission, and the first of NASA's Earth Science Decadal Survey missions. (The Decadal Survey, conducted by the National Research Council (NRC),  evaluates what the most important areas of scientific study are for the next ten years). SMAP is greatly influenced by the NASA Hydros mission, which had similar goals but was cancelled in 2005 due to a lack of funding. 


SMAP was developed to gather data about the conditions of Earth's soil moisture, and how it changes through its freezing and thawing states.  This information is gathered by the satellite's high-res global mapping of the top 5 cm of Earth's surface, which is measured every 3 days. The data collected can be applied to the conduction of more accurate weather forecasts, agricultural production, flood & drought warnings, human health (in terms of vector born diseases and water supply), and studies of climate change.  What I found most significant about SMAP is that the data effects the whole world (and is available to the whole world) not just coveted by one governmental organization. This fact highlights the importance of facilitating a global movement to fight climate change and understand what is actually happening to our planet. The use of SMAP emphasizes our need to unite as a species and educate ourselves in order to be a positive influence on our ecosystem -- instead of blindly destroying it.  
  

The part of the "Instrument" that I was most interested in was the antenna, which was explained to us by Wendy Edelstein. The antenna is connected to the body of the satellite with an arm that extends to support a spinning reflector. The parabolic reflector is optically transparent but can appear opaque depending on how it interacts with the light. My first impression was that the reflector looked extremely delicate, made of a mesh material that didn't look like it could withstand the conditions of outer space, (ex. encounters with rocky debris & whatever else is orbiting around earth up there). However, Wendy confirmed that JPL has conducted enough tests and experiments to conclude that the material is functional, and that possible debris interference is a risk they are willing to take.  The reflector begins as a compacted structure, and expands to be 6 meters wide when released from its compartment. The expansion takes about 30 minutes. The reflector spins at 14 revolutions per minute, capturing 1000 km of land in its swath.